Positive tow target exchanger



July 22, 1952 R. l.. wElR PosITIvE Tow TARGET ExczmummA Filed March 1s, 1951 Patented July 22, FV1952 POSITIVE TOW TARGET EXCHANGER Richard L. Weir, Dayton, Ohio Application March 13, 1951, Serial No.v 215,367

4 Claims.

(Granted under the act of March 3, 1883,`as

amended April 30, 1928; 370 0. G. 757) The invention described herein may be manufactured and used by or for the Government for governmental purposes without payment to me of any royalty thereon.

This invention relates to aerial tow targets of that character whereby a used target is released and replaced with a fresh one during flight.

Current practice in tow target gunnery consists in towing a target by means of a suitable towing plane equipped with a windlass upon which is wound a predetermined length of cable. The target is let out a safe distance by unwinding this cable, and after a prearranged amount of gunnery practice has been had and recorded on a target it is exchanged for another.

It is extremely diilicult to reel in a used target with the windlass because of the air resistance encountered by the target so that it is the present practice to provide mechanism at the trailing end of the towing cable whereby a used target may be released and dropped and replaced by another. The mechanism performing this duty is so constructed that the impact of the new target sent rearward from the tow plane along the tow cable will release the old target but will hold the new one for further gunnery practice, each used target being in turn replaced by a new one through operation of the releasing mechanism of the exchanger.

Tow target release mechanisms of the general character herein disclosed are old in the art but none are as simple in construction nor as effective in operation as could be desired. It is therefore an object of this invention to provide a tow target exchange which is positive in operation, simple in construction and inexpensive to manufacture. I attain this and other objects in the mechanism hereinafter described with reference to the drawings, wherein,

Fig. 1 is an axial section through a device made in accordance with my invention showing the y several movable parts as they appear in normal use.

Fig. 2 is an axial section through the device as the several parts appear when target exchange is being effectuated.

Fig. 3 is a perspective view of the standard cable end which is a partA of each target.

Like reference characters refer to like parts throughout the views.

The targets used in connection with my improved exchanger are conventional and are therefore not shown. Each target is provided with a short length of cable 4 the leading end of which has attached thereto a standard target cable attachment 5, seen in Fig. 3, and which 2 part I2 with an end cap I4 welded thereto along the line I6. A tapered ring-guide member I8 is removably attached to the end cap I4 by screw threaded engagement as at 20. A towing cable 22 is held by one end in the guide member I8 in the usual manner, the other end of the cable being carried on the towing plane. v

The bore 24 of the mainbody part I2 is oil. center and extends from the trailing end through the greater part of its length, while a shorter bore 26 of the same diameter enters, the side of the body part I2 and extends at an angle rearward to meet the longer bore. The short bore 26 should be accomplished before the end cap I4 is welded to the body portion I2.

A plunger 28 is slidable axially in the longer bore 24, and two large steel balls 30 and 30 are freely movable in the longer bore 24 or the shorter bore 26. Two smaller balls 32 and 32 lying in transverse openings 34 and 36 are movable inward and outward by the cams 33 and 43 which are formed on the plunger 28. The outer edges of openings 34 and 36 are peened to limit outward movement of the balls 32 and 32'. A spring 42 is held under ycompression by the threaded plug 44, whereby the plunger 28 is forced against the ball 30, the ball 3l) against the ball 30 and the ball 30' against the surface 46 (see Fig. l).

The operation of my improved tow target exchanger is substantially as follows:

With the tow cable 22 reeled all the way in and the exchanger II removed, as by unscrewing the threaded part 20, a series of cable ends 5, Fig. 3, each with a short 4cable and a target attached, may be strung onto the tow cable over the member I8, after which the member I8 Vand the exchanger II may again be screwed together.

The last one of the target cable ends 5 to be strung on the tow cable will now be moved rearward over the exchanger, being stopped by the ball 32 at the position designated by the numeral comprises a yoke 6 to which the short cable 4 is 43. Tow cable may now be payed out to a predetermined length consistent with safety and the rst target is ready for gunnery practice.

When the regulation number of shots has been red at the rst target, the second target must be launched to cause the rst target to be dropped. As the ring assembly 5 ofthe second target moves backwardly of the tow plane travel, it rst passes the position designated by the numeral 5I), Fig. 2 whereby the ball 30' is moved inwardly, thereby pushing the ball 30 and plunger 28 rearwardly against the compressive resistance of the spring 42, and coincidentally the cam 38 pushes the ball 32 radially outward while the cam 40 allows the ball 32 to move radially inward thereby allowing the ring 5 to slide off the rear end of the exchanger thus dropping the used target. Fig. 2 shows al1 of the balls in the positions they occupy at the instant the ring 'l 3 of the cable end 5 is passing over the highest point on the large ball 30.

As the ring 'l of the cable end 5, Fig. 2, is drawn rearward oi the ball 30', the spring 42 returns the plunger 28 and balls 30, 30', 32 and 32' to their inactive position Fig. 1. However, ring 't of the cable end 5, Fig. 2 may move so rapidly rearward that it will contact the ball 32 before the return movement of the plunger 28 can remove the cam 38 from under the ball 32, in which case the ring 1 will momentarily hang up on the ball 32 until the plunger 28 has continued its forward movement, whereby the cams 38 and 40 will have moved the ball 32 clear in and the ball 32 clear out, whereby the ring 1 of the target end 5 will pass over the ball 32 and be hung up by the ball 32 (see position 48, Fig. 1) ready for the next round of gunnery practice. Obviously if the movement forward of the plunger 23 lags behind the movement rearward of the ring 1 of the target end 5, the ring 1 will be detained by the ball 32 until the ball 32 has moved outward to a position where it will retain the ring 1 in the position 48.

When the foregoing sequence of operations is repeated until the last of the targets has been sent back from the towing plane and has attached itself to the changer and has subsequently been practiced upon, the last target is released by sending baci; from the towing plane a target of much less size and weight so that, after it attaches itself to the exchanger in the usual manner, i. e., by detaching the last sent practice target, the light weight target may be reeled in with the tow cable and removed manually. The light weight target should be of suioient weight to keep the tow cable from whipping as it is being reeled in.

The invention hereinbefore described has several advantages. vIt is simple in construction whereby it may be produced without expensive special tools. It is inexpensive to build, no high cost material being required. It is certain in operation since a new target cannot be attached except by the act of discarding the old one. It is self energizing since the spring which actuates the cams is compressed by movement of a new target into operative position.

Having described an embodiment of my invention, I claim:

`1. A tow target exchanger comprising an elongated body having a main bore extending parallel with the axis of said body and part way through said body, and a continuation 0I" said main bore at an angle with said axis, whereby said continuation bore emerges through the side of the said elongated body, a plunger slidable axially in'said main bore, a rst ball protruding part way from and slidable in said angular bore, a second ball freely held between the end of said plunger and the said first ball and normally in said angular bore but slidable into said main bore by inward displacement of said rst ball, first and second axially spaced apart balls slidable in transverse openings in said body, and cams formed on said plunger in contact with said first and second axially spaced apart balls so formed that when said plunger moves in one direction the first axially spaced apart ball moves transversely inward and the second axially spaced apart ball moves transversely outward and when saidplunger moves in the other direction, said second axially spaced apart ball moves transversely inward and the first axially spaced apart ball transversely outward, and resilient means 4 in said bore urging said'plunger against said second ball.

2. In a tow target exchanger, an elongated body, a main bore entering said body at the rearward end and passing lengthwise part way through said body then continuing along an auxiliary axis which makes an acute angle with the main bore axis until said continuation emerges from the side and front end of said body, a cap covering that part of the auxiliary bore which emerges from the end of said body, a plunger slidable axially in said main bore, a irst ball protruding part way from and slidable in said angular bore, a second ball freely held between the end of said plunger and the said first, ball, and normally in said angular bore but slirlable in said main bore by inward displacement o said rst ball, rst and second axially spaced balls slidable in transverse openings in said body, and cams formed on said plunger in contact with said iirst and second axially spaced apart balls so formed that when said plunger moves in one direction, the rst axially spaced apart ball moves transversely inward and the second axially spaced apart ball moves transversely outward, and when said plunger moves in the other direction said second axially spaced apart ball moves transversely inward and the first axially spaced apart ball transversely outward, and a resilient means in said boreurging said plunger against said second ball.

3. In a target exchanger, an elongated body, a plunger slidable longitudinally in said body, operating means protruding from one side oi said body pressible transversely inward to move said plunger axially in one direction, resilient leans for moving said plunger in the other direction, two axially spaced members slidable transversely in said' body, and cam surfaces formed on said plunger adjacent said members, operative, when the plunger moves in the one direction, to move one of said members out and allow the other said member to move in, and operative, when the plunger is moved in the other direction, to move the said other of the said members out and allow the said one of the said members to move in.

4. In a target exchanger, an elongated body, a plunger slidable lengthwise in said body, two latching members movable crosswise in said body, cams carried by said plunger and associated with said latching members, and adapted, when the plunger is moved lengthwise in one direction, to force one latching member out and allow the other latching member to move in, and adapted when said plunger is moved lengthwise in the other direction to force the said other latching member out and allow the said one latching member to move in, and means operable crosswise of said body to move said plunger lengthwise.

RICHARD L. WEIR.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 1,971,340 Foulk Aug. 28,1934 2,310,249 Maskey Feb. 9, 1943 2,376,754 Brickman May 22, 1945 2,382,854 Brickman Aug. 14, 1945 2,435,980 Pyle Feb. 17, 1948 2,492,154 Jessen Dec. 27, 1949 

